Warning: While not always a Death Trope, can often involve that, so be wary of spoilers.
Heel-Face Door-Slams in Western Animation.
- Arcane: For most of the season, the Piltover City Council members have shown themselves to be corrupt and selfish elists. In the final moments of the Season 1 finale, they unanimously vote for peace and accept Silco's extremely favorable terms for an independent Zaun. Seconds later, Jinx's Hextech-powered rocket strikes their chambers, leaving their fate uncertain but peace off the table.
- Avatar: The Last Airbender:
- Fire Lord Sozin is a textbook definition of this trope. He wasn't all evil, but by the time he came to the realization that his actions were evil (leaving his best friend to die, committing genocide and launching a world war) and not worth it in the end, he was on his death bed, and his descendants largely carried on his genocidal work, while also dropping all the decent intentions that motivated him to his evil actions.
- Jet starts out as a Well-Intentioned Extremist, but through a series of events, he's brainwashed by the Dai Li. When he finds out that he was brainwashed in "Lake Laogai", he helps the GAang storm the Dai Li base under Lake Laogai until Long Feng activates a secret code phrase that causes Jet to attack Aang. Aang breaks him out of his brainwashing long enough for Long Feng to clobber Jet with a rock before escaping. An injured Jet ensures his friends that he'll be fine, but Toph knows he's lying.
- Batman Beyond: In "Meltdown", Mr. Freeze has his mind transferred to a new cloned body. Restored to normal, he tries to make a new life for himself and help the victims of his crimes. However, his body begins to revert to its cold-dependent state, and the doctor who did the procedure tries to kill him for study rather than help him. He escapes and goes back to his old revenge-seeking ways.
- Batman: The Animated Series: In "Birds of a Feather", after the Penguin is released from prison, Veronica Vreeland, a wealthy socialite, pretends to have a crush on him on urging from her friend, both of them thinking that associating with him will be good PR. The Penguin is actually happy for a while and considers going straight and giving up crime... until he realizes that he's being used. Out of rage, he kidnaps Veronica and tries to kill her friend when he delivers the ransom. Once Batman apprehends him, she feels a little sorry for it all and tries to apologize, to which the Penguin responds: "I guess it's true what they say; society is to blame. High society."
- Ben 10: Invoked in the episode "Framed". During their second showdown, Kevin mockingly asks Ben if he just wants to try to help him; Ben promptly informs him that he's done trying to help Kevin, especially since Kevin had plenty of chances to get help before, and refused to take them.
- BoJack Horseman: In a Season 2 flashback that shows Sarah Lynn around 7ys/o, she asks BoJack where he went to college and expresses that she wants to be an architect when she grows up. Flash forward to the Season 3 episode "That's Too Much, Man!" — throughout her month-long bender with BoJack, she gradually starts realizing how much she hates fame and what it's made her. She wonders how allowing children to act is even legal, equating it to child labor ("I didn't know what I was signing up for. I was three.") She expresses how nothing she does it /her/ right after winning an Oscar. BoJack takes her to the planetarium to calm her down, as she'd been suggesting they do the entire time, and she clues him in that it's not actually the trippy visuals that make planetariums interesting to her — it's the domed design. She dies in BoJack's arms, her last words:Sarah Lynn: I wanna be an architect.
- Carmen Sandiego: Carmen's father was one of V.I.L.E.'s top agents, and part of the organization's leadership. After the birth of his daughter, however, he tried to leave the organization so he could raise her peacefully, only to be killed in an Interpol raid before he could.
- Codename: Kids Next Door: Happens to both Father and The Delightful Children From Down The Lane in Operation: Z.E.R.O.:
- Father tries to redeem himself for causing the events of the film by joining forces with his younger brother to defeat their dad, but he immediately chickened out and went back inside to eat ice cream. He goes back to his evil ways after the events of the film never to attempt redemption ever again.
- The Delightful Children From Down The Lane were cured from their delightfulization and recommissioned as the missing operatives of Sector Z. Unfortunately, since any reversion is temporary due to the delighfulization being permanent, they forcibly revert back to their delightfulized selves ruining their only chance at freedom.
- The Dragon Prince
- Lord Viren
- Once King Harrow calls him out on how unethical he's become, it's implied Viren is preparing to make a Heroic Sacrifice to die in Harrow's place. Then Harrow misunderstands Viren's intentions and verbally rips him apart. Afterwards, whatever plans for redemption Viren had are abandoned in favor of gaining power for himself.
- Self-inflicted in season 5. After Claudia brought him back to life last season, he began soul-searching about his actions and use of dark magic, ultimately realizing he went too far and that he risks dragging Claudia and Soren down with him, so he refuses to help Aaravos escape prison and allows the resurrection spell to expire naturally.
- Lord Viren
- DuckTales (2017): At the climax of "The Duck Knight Rises!", Jim Starling is preparing to kill the actor that replaced him in his most famous role when Launchpad interrupts with a Rousing Speech. Said speech (as well as the replacement's assertion that Launchpad is his biggest fan) induces a Heel Realization in Jim, leading to him seemingly sacrificing himself saving Launchpad and the replacement from an explosion. He doesn't die; however, that ended up becoming the last heroic act he performed before his mind was warped permanently, turning him into Negaduck.
- After the Evil Con Carne organization went out of business, Skarr just wanted to retire to a quiet house in the suburbs, where he could relax and do some gardening. Unfortunately, he moved right next to Grim, Billy, and Mandy, making his new leaf very hard to keep.
- The Fairly OddParents!:
- Taken to ridiculous extremes in the TV Movie Channel Chasers. At the end of the movie, Timmy's Sadist Teacher Mr. Crocker was seen coming out of therapy, cured of his fairy obsession, and decides to turn his life around. He even discovers a cold fusion! Then, even though he had nothing to do with the episode plot (in fact, his very appearance was probably just to show that he is a Cosmic Plaything), Timmy's wish that nobody remembers anything that happened affected him, reverting him back to his fairy-obsessed self who tosses away his cold fusion because he doesn't know what it is anymore.
- Done again in the episode "Crocker Shocker" where Mr. Crocker is put under hypnosis by a desperate therapist to erase his belief in fairies. Among the changes he undergoes, he loses his hunchback loses and his ears moved from his neck to his head. Unfortunately, it turns out the Fairy Magic is powered by Crocker's fairy-believing spazz attacks, so Timmy had to get him back to his old self. You know the universe is unfair when one person's sanity has to be sacrificed.
- Final Space: Gary's mother Sheryl experienced this in the past. She was originally a spy who only got close to Gary's father to supply his confidential Infinity Guard plans to her employers, but she began settling down and experiencing Becoming the Mask although she still supplied her employers with info. When John found out, he was hurt and horrified (not least by the fact Sheryl had a child with him supposedly just as part of her job) and kicked her out. This led to Sheryl, who pinned all the blame for this on her son, being absent from Gary's life, and ultimately being manipulated by the Titan Oreskis into becoming an antagonist to her son and his team during Season 2.
- Futurama: In "Benderama", a huge ugly giant with anger management issues chases the main characters off his planet after Fry accidentally insults his mother. Later, a bunch of microscopic self-replicating Benders convert Earth's water supply into alcohol, leaving the planet drunk. When the giant lands on Earth to apologize for his actions, the gang is hammered and drunkenly crack ugly jokes again. This puts him over the edge, causing him to ravage New New York before being put down by the microscopic Benders.
- Simon Squealer in Geronimo Stilton experiences this thanks to a combination of Negative Continuity and Status Quo Is God. He pretends to be a superhero called the Gator Samaritan in one episode, and the heroic acts he performs are staged to sell issues of The Daily Rat. But after he rescues Thea Stilton from drowning, he realizes Good Feels Good and starts disobeying Sally and performing genuinely heroic acts independently of her paper-selling scam. Although Thea is grateful enough to him that she lets him go after he's outed as a phony, and he is clearly feeling morally conflicted over his continued involvement with Sally, the episode closes with him still under her thumb (complete with a humiliating joke at his expense), and, the next time he appears, he's back to his old sniveling, weaselly self.
- Heckle and Jeckle give up practical jokes as a New Years resolution in 1961's "Sappy New Year." But when their attempts to do good deeds are misconstrued as more of their mischief, Heckle tries to revert back.
- Jem:
- After a near-death experience, Stingers keyboardist Minx vows to become a better person. But even though she meant well, Minx was a bit overbearing and in particular Aja was unwilling to forgive her or accept her change, though some of the things that went wrong when she tried to help weren't really her fault. She reverted back to her old personality after she was told she doing "too much". Fortunately, she redeems once more in the series finale.
- A self-invoked version happened to Clash, The Misfits' designated groupie. In a final attempt to join the band, she disguises herself as a student making a documentary on The Holograms and in essence tries to record them at their worst moments and ruin theirs and her director cousin Video's career. However, in seeing how welcoming they are to her and accidentally getting footage of The Misfits at their worst instead, she is exposed and while the Holograms are still willing to accept her, she rejects them, refusing to believe that the Misfits aren't her friends. Her last moment of the series has her begging the band to let her be their friend and they drive off, leaving her alone.
- The Johnny Bravo episode "Blanky Hanky Panky" has an eccentric villain in a cat costume called Felinius attempt to destroy Aron City by stealing all the city's yarn and wool and using it to create a gigantic ball of yarn he intends to crush the city with. After he is defeated by Johnny, he sees the error of his ways, but this doesn't spare him from being tarred and feathered by Johnny's mom and the other women who wish to punish him for stealing all the yarn.
- King of the Hill: "Pigmalion" sees Luanne meet Trip Larsen, a crazy pork magnate who wants to become her pet pig. He chases her onto a slaughterhouse conveyor, where he's shocked by a hog stunner, making him lucid. But his newfound clarity ("The voices have left my head... what am I doing in a pig costume?") is short-lived; the conveyor drags him to his doom.
- My Dad the Bounty Hunter: Glorlox, a ruthless bounty hunter and Terry AKA Sabo Brock's former partner, spends the majority of the series shadowing Sabo, convinced that Sabo and his "new partners" Lisa and Sean are hunting a high paying bounty, and intending to beat Sabo to capturing the target and taking the bounty for himself. At the end of episode 8, Glorlox destroys Sabo's ship, and takes Lisa, Sean, and Vax into custody. Upon learning that Lisa and Sean are actually Sabo's daughter and son, Glorlox shows regret for having separated children from their father. Although it's possible that Glorlox was still at least partially motivated by greed since his last push over the edge was when The Fixer only offered him 15% of the pay that had been promised to Sabo, he appeared to have made a Hell-Face turn when he helped the heroes escape from the custody of The Conglomerate in episode 9. Glorlox appeared genuinely happy to be able to fight alongside his former partner Sabo again. However, the door-slam occurred when they all reached his ship. Sabo thanked Glorlox for the rescue before shoving Glorlox off of the ship and taking off without him as revenge for Glorlox having captured his children in the first place, leaving Glorlox stranded aboard The Conglomerate's ship to face whatever punishment they had in store for him.
- In the Disney Direct to Video Compilation Movie Once Upon a Halloween, an unnamed villain obscured in shadow plots to take over Halloween and her cauldron shows her visions of other villains committing evil deeds. Upon seeing clips of the villains' defeats, she decides she doesn't want to go through with her plan anymore, but then the cauldron pulls her into itself, essentially punishing her for simply planning an evil scheme before she could do it.
- In ReBoot, the treacherous binome Cyrus was on the point of a Heel–Face Turn at the end of "Firewall" after the protagonists guided him through saving the day from the Game Cube Of The Week. He was in the middle of being lauded as a hero when the Big Bad showed up and had his goons drag him onto their side of the eponymous impenetrable wall; a couple episodes later he was shown about to be executed. One of the goons set him free, but he still didn't show up again until a cameo at the end of the season.
- Robot Chicken: In "Robot Chicken DC Comics Special 2: Villains in Paradise", Starro attacks both the Justice League and the Legion of Doom and kicks everybody's asses. Thinking they are about to die, Superboy and Lena Luthor declare their love for each other. Starro is touched by this and starts saying he will stand down, only for Batman to impale him with a boat construct made by Green Lantern.
- One episode of Samurai Jack features the robotic assassin X9, who was one of several murderous robots created by Aku, but was the only one given emotions and feelings (As he explains it, the scientist who built him "was funny like that"). After years in the service of Aku, all the other robots of his series have been destroyed, but he has survived because of his emotions. However, when he meets Lulu he finally hangs up his assassin hat for good, determined to settle down and spend his time playing music. Unfortunately, when Jack arrives, Aku becomes desperate and decides that he has to pull his greatest assassin out of retirement by holding Lulu hostage. Jack knows nothing of this, and when X9 launches his attack he is quickly destroyed, his final words are asking Jack to finish caring for his now abandoned charge. Also notable for being one of the saddest things in the entire show.
- The Simpsons:
- In "Brother from Another Series", Sideshow Bob truly does go straight, and with Bart and Lisa's help, foils the scheme of his brother Cecil. Due to Chief Wiggum's utter incompetence, Bob is mistaken for Cecil's accomplice and sent back to prison. Bob would never again try to reform.
- The closest Mr. Burns ever came to turning over a new leaf was in "Rosebud". After trying every underhanded way he could think of to force Homer to give him his teddy bear Bobo (and finally hitting rock-bottom by trying to take it from Maggie by force and failing) he gave up; at which point Maggie gave it to him. Leading to this exchange:Burns: Smithers, I'm so happy. Something amazing has happened, I'm actually happy. Take a note! From now on, I'm only going to be good and kind to everyone.Smithers: I'm... sorry sir, I don't have a pencil.Burns: Oh, don't worry, I'm sure I'll remember it.
- Smiling Friends has the Frowning Friends. At the end of their debut (and, as it soon turns out, only) episode, they finally smile for the first time and decide that they enjoy it. Just as it looks like they'll break away from their attempts to spread misery and hatred throughout the world, however, they are killed by the Renaissance Men, who show up out of nowhere and baffle the characters with their sudden appearance.
- The South Park episode "Free Hat" deals with filmmakers making revisions to their films with Steven Spielberg and George Lucas as villains. Lucas briefly ponders giving the copy of Raiders of the Lost Ark to the boys so that they can protect it from Spielberg. However, when Spielberg demands that Lucas give him the film, he relents before complying. As he does so, he comments "It is too late for me". He is later killed along with Spielberg and Francis Ford Coppola when said film is poorly received at its premiere.
- Star Wars Rebels: In "The Siege of Lothal", Minister Maketh Tua not only realizes that she is at risk of terrible punishment for failing to stop the Rebels despite being a civilian official with neither the authority nor expertise to deal with such military threats, but that the Empire she's served so loyally is the type of government that would kill its own people for such reasons. She makes arrangements to defect to the Rebellion and deliver valuable intelligence to them ... and then her shuttle is blown up to frame the Rebels for her assassination before she's even able to turn over her information.
- Steven Universe episode "Change Your Mind" has this nearly happen to Yellow Diamond and Blue Diamond, but especially to the former. When they try to save Steven from White Diamond and then try to appeal to her for the Gem Empire not to be run with an iron fist, her response is to blast them with Projectile Spells and turn them into monochrome puppets completely under her control. Thankfully they get better later when White has her own Heel Realization.
- In Teen Titans (2003), Terra makes a Face–Heel Turn and joins Slade, becoming The Mole to the Titans. However, due to getting close to the Titans, she ends up regretting her actions but doesn't dare to fully betray Slade. She just tries to spare Beast Boy, taking him on a date while Slade's army infiltrates the Titan Tower. Slade tracks Terra and Beast Boy down, revealing the truth to Beast Boy. An apologetic Terra breaks down sobbing, saying she's sorry and pleads with Beast Boy to forgive her, reminding him he said they'll be friends no matter what. An angry Beast Boy responds with "Slade's right. You don't HAVE any friends." As a result, Terra fully embraces being Slade's apprentice and becomes truly evil, and Beast Boy ends up kicking himself over slamming the door in her face earlier. In the end, however, Terra makes a Heel–Face Turn after all...but with a cost.
- Transformers: Prime:
- Starscream gets so sick of being the Decepticon's Chew Toy that he tries to defect to the Autobots. Note that Starscream is not in any way repentant, he just figures he has a better chance on their side. Once it's revealed that Starscream killed Cliffjumper, Arcee goes ballistic and tries to avenge her dead partner. Starscream is driven off and is convinced that he should become a neutral party in the war.
- In the TV movie, Knock Out tries to do the same thing. He even has the same reasons at first. But unlike Starscream, he actually does try again, showing that he means it.Arcee: Why'd you do it, Knock Out? Why'd you turn against Starscream?
Knock Out: Even if I had helped him seize this ship, he would probably just fire me out of the first airlock. Oh. And he's rude.
